A plasma display panel (PDP) device is a representative large-screen full-color display device. A plurality of display electrode pairs for inducing surface discharge are formed on a display-side substrate (front substrate) of the PDP, while address electrodes perpendicular to the display electrode pairs, stripe-shaped barrier ribs and fluorescent layers covering them are formed on a back-side substrate (back substrate).
The PDP is driven as follows. Namely, a large voltage is applied to a display electrode pair to reset, and discharge is induced between one of the display electrode pair and the corresponding address electrode. By utilizing a wall charge generated by the discharge, a sustaining voltage is applied between the display electrode pair to cause sustaining discharge.
This display electrode pair is used as scanning electrodes for plasma discharge, and a transparent dielectric layer, typically, with a thickness of from 20 to 30 μm is formed thereon for sustainment of discharge.
Each of the scanning electrodes is normally composed of a transparent electrode of ITO or the like and a bus electrodes such as a Cr—Cu—Cr electrode and an Ag electrode formed on a part of a surface of the transparent electrode.
A low melting-point glass containing PbO has been used for the transparent dielectric layer, but electrode-covering low melting-point glasses containing no PbO were recently proposed (cf. JP-A-2004-146357 and JP-A-2001-195989).
JP-A-2004-146357 proposed nonlead glasses containing, in mass %, BaO 3-25%, ZnO 25-60%, B2O3 15-35%, SiO2 3-30%, Li2O 0.2-6% and Al2O3 0-1.5% for the purpose of making bubbles less likely to remain in the dielectric layer and preventing large bubbles from remaining near the electrode.
JP-A-2001-195989 proposed nonlead glasses containing ZnO and an alkali metal oxide of at most 10% by weight and having a low permittivity for the purpose of avoiding increase of power consumption even in a larger-sized screen and higher resolution.